The first thing to know about Mekong Cafe is that the front door isn't a front door.

I mean, sure, it's technically a functioning door. And it has the restaurant's hours posted on it, as if they expect people to, you know, walk through it.

But when my friend, Heather, and I tried to use that door upon arriving at Mekong Cafe for a weekday lunch, it was locked.

We were confused. We peered into the windows, which are tinted, and could just make out the shadowy shapes of people sitting at tables, eating.

Obviously, the place was open.

After we stood there a moment longer, a server came to the door-that's-not-a-door and let us in, relocking the door behind us. "That's not the door," she said. "The back is the front door."

That would be the door off the back parking lot, so if you try Mekong Cafe — and it's worth trying — don't bother walking around to the front. Like I said, it's not the door. (Note to Mekong's proprietors: a sign on the door informing patrons of this fact might be helpful.)

But most other things at this little Thai/Vietnamese/a bit of Chinese eatery are just about what they should be: very good Thai food served in an intimate, interesting setting by a staff that knows what it's doing.

There aren't many tables at Mekong, but the space is cunningly arranged to be comfortable, pretty and relatively private for each group of diners, with just enough Thai notes — elephant light sconces, a few pieces of sculpture — to impart an exotic vibe.

One thing I never like about eating Thai for lunch is that my usual instinct to order tons of food and take loads home for later goes to war with the fact that it's just lunch, and I simply won't be able to eat very much.

I decided to forego one of my usual staples, the tom kha gai soup, but I kept my usual order of chicken satay.

Heather, who likes Thai food but hasn't had much of it, had never tasted satay, and I was glad Mekong's was so good: big flat skewers of tender, lean chicken seasoned golden and seared brown, served with peanut sauce and sweet vinegar sauce full of cucumbers that I fished out of my portion and ate like salad.

We also had the green papaya salad, one of the true culinary treasures of Thailand, with its green shredded papaya, onions, tomatoes and carrots with ground peanuts in a spicy dressing. Mekong has several spice levels: mild, medium, hot and "authentic."

We had medium for the salad, and it gave a spicy punch to the salad's cool, sweet crunch, though I think I'd go hotter next time.